Plants and Ecosystems (PLECO), Department of Biology, University of Antwerp, Belgium
Mechanisms underlying ecosystem functioning that are currently mostly observed in drylands may become more relevant also in historically less water-limited regions under ongoing climate change. This is likely particularly related to increases in climate extremes, especially heat waves and droughts. However, we currently lack data that clarifies which mechanisms are likely to change the most, what the shape of their response curves is (e.g. linear or threshold-based), and how they relate to mechanisms currently common in non-dryland regions, i.e. how much of their function “dryland mechanisms” could replace under changing environmental conditions. Experiments are valuable tools that can provide such data, as they allow to control abiotic and sometimes also biotic conditions to varying extent, making it possible to test specific hypotheses, uncover response curves, etc. Multiple approaches exist, and we will here discuss which designs and technologies are especially suited for research into emerging dryland mechanisms. This also encompasses being aware of drawbacks and ways to circumvent these, although some issues are inherent and cannot be avoided altogether. Even then, choices can be made to ensure that experimental artifacts do not become detrimental to the conclusions of a study. We hope that outlining both the challenges and the opportunities regarding the experimental study of dryland mechanisms will motivate global change ecologists to incorporate these mechanisms into their research. Shedding light on this largely unexplored field is worthwhile not only from a fundamental science perspective, but can also help guide efforts to make (managed) ecosystems more resilient in the face of climate extremes.
